The present invention relates generally to a seat belt for a seat in a moving vehicle and more particularly to a mechanism for a seat belt which allows the seat belt to raise and lower with the occupant as the seat is adjusted vertically.
There are many variations in vehicle occupant restraint systems. In one such vehicle restraint system, a seat belt is used which consists of a lap belt and a shoulder belt that merge at a clasp structured to releasably engage a manual buckle mechanism or assembly. The buckle is typically attached to the underbody of the vehicle to function as an anchor when the occupant restraint system is in use. The buckle is normally positioned at or near the seat cushion or pan on the inboard side of the seat for easy accessibility when joining or disjoining the seat belt and buckle assembly.
In many of the vehicles designed today, the occupant is provided with a power seat adjustment feature, which allows the occupant to adjust the seat both horizontally and vertically to position or orient the occupant in a comfortable position. However, as the seat rises a distance vertically, the seat belt cannot accommodate the change in vertical distance. Consequently, the lap belt begins to tighten or pinch the occupant which makes it uncomfortable. This problem is not limited to the seat belt described above.
The prior art has attempted to address this concern. One example of a mechanism used to accommodate vertical and horizontal seat movement is shown in U.S. Pat. No. 3,977,725. While such a mechanism may accomplish the desired task, it was designed for a suspension seat for a truck wherein the seat experiences large vertical travel. For this reason, the mechanisms for supporting/moving the seat and for adjusting the seat belt employ an elaborate and sizable set of components. However, in vehicles with limited seat space and motion such as automobiles, these components are neither acceptable nor required. Space is a greater concern for those vehicles that employ power seat adjustment components.
Now, for those vehicles that do provide such power seat adjustment features, there does not exist a simple and space saving design for seat belt adjustment components that will function simultaneously with the power seat adjustment components. It follows that there does not exist a design for seat belt adjustment that minimizes or even eliminates damage to the power seat adjustment components resulting from a crash load.
It would therefore be desirable for a vehicle to employ a mechanism that allows the seat belt to raise and lower with the occupant as the seat is adjusted vertically which overcomes the drawbacks of the prior art described above.
An object of the present invention is to provide a mechanism for a seat belt that allows the seat belt to raise and lower with the occupant as the seat is adjusted vertically that overcomes the disadvantages of the prior art.
Another object of the present invention is to provide a mechanism for a seat belt that allows the seat belt to raise and lower with the occupant as the seat is adjusted vertically which uses fewer components so that the mechanism fits within a confined space in an automobile.
Another object of the present invention is to provide a mechanism for a seat belt that allows the seat belt to raise and lower with the occupant as the seat is adjusted vertically which reduces or eliminates damage to power seat adjustment components as a result of a crash load.
These objects and other objects are accomplished by the present invention described in the following detailed description of the preferred embodiment, taken generally with the Figures.
Generally, however, the present invention provides a seat apparatus for a vehicle comprising a first mechanism for moving a seat horizontally relative to the floor of the vehicle and a second mechanism movably mounted to the first mechanism for moving the seat vertically relative to the floor of the vehicle. The second mechanism includes at least one link for supporting the seat and a motor drive assembly operatively associated with the link to move the seat vertically. The seat apparatus further includes a third mechanism for moving a seat belt to adjust for vertical movement of the seat in order to insure that the seat belt will remain stationary relative to an occupant seated on the seat. The third mechanism is responsive to the motor drive assembly for moving the seat belt simultaneously with vertical movement of the seat.
The present invention also provides a seat apparatus for a vehicle comprising a first mechanism for moving a seat horizontally relative to the floor of the vehicle. The mechanism includes first and second lower tracks mounted to the floor of the vehicle and first and second upper tracks movably carried on the first and second tracks, respectively. The seat apparatus also comprises a second mechanism movably mounted to the first and second upper tracks for moving the seat vertically relative to the floor of the vehicle. The second mechanism includes (1) a pair of lift links for lifting the seat and (2) a drive motor assembly operatively associated with the lift links for causing the pair of lift links to move the seat generally vertically. The seat apparatus further comprises a third mechanism for moving a seat belt to adjust for vertical movement of the seat in order to insure that the seat belt will remain stationary relative to an occupant seated on the seat, of the third mechanism including (1) a first seat belt link pivotably attached to the first upper track and (2) a motor drive assembly operatively associated with the first seat belt link to cause said seat belt link to pivot.